Julian Date Conversion

Calculate Julian date or modified Julian date

• 

Libraries:
Aerospace Blockset / Utilities / Unit Conversions

Description

The Julian Date Conversion block converts the specified date to the Julian date or modified Julian date.

Limitations

• This block is valid for all common era (CE) dates in the Gregorian calendar.

• The calculation of Julian date does not take into account leap seconds.

Ports

Input

day — Clock source

scalar | array

Clock source for model simulation, specified as a scalar or array.

Dependencies

The presence and label of this port depends on the Time increment parameter.

Port	Time increment Setting
day	Day
hour	Hour
min	Min
sec	Sec
No inport port	None

Data Types: double

Output

JD — Julian date

scalar | array

Julian date, returned as a scalar or array.

Dependencies

Data Types: double

Parameters

Year — Year

2013 (default) | double, whole number, greater than 1

Year, specified as a scalar, to calculate the Julian date.

Programmatic Use

Block Parameter: year

Type: character vector

Values: double, greater than 1

Default: '2013'

Month — Month

January (default) | February | March | April | May | June | July | August | September | October | November | December

Month to calculate the Julian date. From the list, select the month from January to December.

Programmatic Use

Block Parameter: month

Type: character vector

Values: 'January' | 'February' | 'March' | 'April' | 'May' | 'June' | 'July' | 'August' | 'September' | 'October' | 'November' | 'December'

Default: 'January'

Day — Day

1 (default) | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31

Day to calculate the Julian date. From the list, select the day from 1 to 31.

Programmatic Use

Block Parameter: day

Type: character vector

Values: '1' | '2' | '3' | '4' | '5' | '5' | '6' | '7' | '8' | '9' | '10' | '11' | '12' | '13' | '14' | '15' | '16' | '17' | '18' | '19' | '20' | '21' | '22' | '23' | '24' | '25' | '26' | '27' | '28' | '29' | '30' | '31'

Default: '1'

Hour — Hour

0 (default) | double greater than or equal to 0 and less than 24

Hour used to calculate the Julian date, specified as greater than or equal to 0 and less than 24.

Programmatic Use

Block Parameter: hour

Type: character vector

Values: double greater than or equal to 0 and less than 24

Default: '0'

Minutes — Minutes

0 (default) | double greater than or equal to 0 and less than 60

Minutes to calculate the Julian date, specified as a double greater than or equal to 0 and less than 60.

Programmatic Use

Block Parameter: min

Type: character vector

Values: double greater than or equal to 0 and less than 60

Default: '0'

Seconds — Seconds

0 (default) | double greater than or equal to 0 and less than 60

Specify the seconds used to calculate the Julian date, specified as a double greater than or equal to 0 and less than 60. Enter a number from 0 to 60.

Programmatic Use

Block Parameter: sec

Type: character vector

Values: double greater than or equal to 0 and less than 60

Default: '0'

Calculate modified Julian date — Modified Julian data

off (default) | on

Select this check box to calculate the modified Julian date (MJD) for corresponding elements of the year, month, day, hour, minute, and second.

Dependencies

Selecting this check box changes the output port label to MJD. Clearing this check box changes the output port label to JD.

Programmatic Use

Block Parameter: modflag

Type: character vector

Values: 'on' | 'off'

Default: 'off'

Time increment — Time increment

Day (default) | Hour | Min | Sec | None

Time increment between the specified date and the desired model simulation time. The block adjusts the calculated Julian date to take into account the time increment from model simulation. For example, selecting Day and connecting a simulation timer to the port means that each time increment unit is one day and the block adjusts its calculation based on that simulation time.

If you select None, the calculated Julian date does not take into account the model simulation time. Selecting this option removes the first block input.

Dependencies

This parameter controls the presence and label of output port.

Time increment Setting	Port
Day	day
Hour	hour
Min	min
Sec	sec
None	No inport port

Programmatic Use

Block Parameter: deltaT

Type: character vector

Values: 'Day' | 'Hour' | 'Min' | 'Sec' | 'None'

Default: 'Day'

Action for out-of-range input — Out-of-range block behavior

None (default) | Warning | Error

Out-of-range block behavior, specified as follows.

Action	Description
None	No action.
Warning	Warning in the Diagnostic Viewer, model simulation continues.
Error (default)	Error in the Diagnostic Viewer, model simulation stops.

Programmatic Use

Block Parameter: errorflag

Type: character vector

Values: 'None' | 'Warning' | 'Error'

Default: 'Error'

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2013b

R2026a: Julian Date Conversion block update

The Julian Date Conversion now requires that the hour, minute, and second values are between 0 and the maximum value.

Models created before R2026a with hour, minute, and second values outside these ranges will generate errors.